A variety of valves and taps have been developed and used to dispense a wide range of fluids from various containers. One common application for disposable taps and valves is “bag-in-a-box” products in which a bladder is provided within a cardboard box or other semi-rigid container, and a low cost, disposable tap is provided to dispense fluid from the bladder. Such structures have been used to dispense water and other beverages such as wine or juice, chemicals and other liquids.
In bag-in-a-box assemblies, the valve component desirably is formed inexpensively, from low cost materials, since the entire packaging assembly, including the valve, is intended to be discarded once the content of the bladder has been dispensed. Of course, the valve must still operate effectively, to tightly close and prevent spills or leakage even after long periods of use with frequent or infrequent opening and closing cycles.
One problem associated with such tap or valve assemblies is the ease with which they can be operated to dispense fluid from the disposable bladder. Some of the known designs require the use of several fingers of one or both hands to operate an actuation button or lever efficiently. Some designs require the user's hands to be placed in an awkward position. Furthermore, some of these assemblies require a separate movement from the user to close the tap or valve in addition to the first movement to open the valve. This, too, can be awkward, requiring repositioning of the user's hand and increasing the risk of accidental spilling or overflowing the container being filled from the dispenser. It is also possible that the user may not completely close the valve, resulting in intermittent dripping of fluid from the valve.
Some known valves provide relatively turbulent output flow, and external spouts are required to control the stream and prevent splashing. External spouts are undesirable in that the valve is necessarily positioned at the bottom of the container, and a spout of any significant length may project past the bottom of the container. For the container to sit flat, a long spout must be positioned at the front edge of a shelf, table or other support to hand beyond it.
What is needed is a valve or tap assembly that can be operated easily, closes automatically and securely, yet can be provided at reasonable expense.